Weldable fuel tank valve apparatus

ABSTRACT

An apparatus is provided that includes a valve assembly and a retainer that couples the valve assembly in a fuel tank. The valve assembly includes a housing having a body portion, a flange coupled to the body portion and retainer blocks extending from the body portion spaced-apart from the flange. A valve is positioned to lie in the housing. The retainer is adapted to be coupled to an exterior surface of the tank. The retainer includes a body portion that defines a passageway sized to receive the body portion of the housing and a ring coupled to the body portion of the retainer and formed to extend into the passageway. The flange and retainer blocks cooperate with the body portion of the retainer and ring to couple the valve assembly and retainer together.

This claims priority under 35 U.S.C. §119(e) of Ser. No. 60/066,838filed Nov. 25, 1997.

BACKGROUND AND SUMMARY OF THE INVENTION

This invention relates to a fuel tank valve apparatus and particularly,to a fuel tank valve apparatus that is suitable for use with a fuel tankconstructed of a polymeric material. Most particularly, this inventionrelates to a valve apparatus that is welded to a fuel tank to mount thevalve assembly in a fixed position in an aperture formed in the fueltank.

Mounting assemblies that are used to mount a venting valve assembly in atop wall of a fuel tank are known. See for example, U.S. Pat. No.4,966,189 to Harris, which is incorporated herein by reference.

According to the present invention, a fuel tank valve apparatus isprovided that includes a valve assembly that has a housing with a bodyportion, a flange coupled to the body portion, a retainer block, and avalve positioned to lie in the body portion. The retainer block extendsaway from the body portion spaced-apart from the flange. In addition,the fuel tank valve apparatus includes a retainer adapted to be coupledto an exterior surface of the fuel tank. The retainer includes a bodyportion defining a passageway sized to receive the body portion thereinand a ring coupled to the body portion and extending into thepassageway. The flange and retainer block of the housing cooperate withthe body portion and the ring of the retainer respectively to couple thevalve assembly and retainer together.

In preferred embodiments, the ring includes a fixed-end portion coupledto the body portion and a ramped free-end portion extending into thepassageway. The free-end portion includes a series of tabs that arespaced-apart relative to one another. Each tab is formed to flexradically outwardly toward the body portion upon engaging an angled camsurface provided on one of the retainer blocks during insertion of thevalve assembly downward through the passageway formed in the bodyportion of the retainer and the aperture formed in the fuel tank wall.

The valve assembly includes a cylindrical housing having an inlet at itsbottom end and an annular mounting flange near its top end and an outletportion coupled to the top end of the housing and formed to include afuel vapor discharge tube. The valve assembly also includes fourcircumferentially spaced-apart retainer blocks and each retainer blockincludes a downwardly facing angled cam surface an upwardly facingretainer surface.

During insertion of the valve assembly into the fuel tank through thepassageway formed in the body portion of the retainer and the apertureformed in the fuel tank wall (after welding the retainer in its mountedposition on the fuel tank wall surrounding the aperture formed in thefuel tank wall), some of the flexible tabs on the ring coupled to themounted retainer are cammed “out of the way” by the downwardly facingangled cam surface on the four retainer blocks to allow the valveassembly to be moved through the passageway formed in the body portionof the retainer to engage the annular mounting flange near the top endof the cylindrical housing against a top end of the welded retainer. Atthis point, the flexed tabs “snap back” to their original positions andengage against the upwardly facing retainer surfaces formed on theretainer blocks to retain the valve assembly in a mounted position inthe retainer that is welded to the fuel tank.

Additional features of the present invention will become apparent tothose skilled in the art upon consideration of the following detaileddescription of preferred embodiments exemplifying the best mode ofcarrying out the invention as presently perceived.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description particularly refers to the accompanying figuresin which:

FIG. 1 is an exploded perspective assembly view of a fuel tank valveapparatus in accordance with the present invention with portions brokenaway, showing a valve assembly, a fuel tank wall formed to include anaperture sized to receive a cylindrical body portion of the valveassembly therein, and a retainer below the valve assembly and above thefuel tank wall; the retainer including an axially upper portionconfigured to be coupled to the valve assembly and a larger diameteraxially lower portion configured to be welded to an exterior surface ofthe fuel tank wall to mount the valve assembly in a fixed position inthe aperture formed in the fuel tank wall;

FIG. 2 is a partial cross-sectional view of the fuel tank apparatus ofFIG. 1 showing the retainer coupled to the exterior surface of the fueltank wall and the valve assembly positioned to lie above and inalignment with a central passageway formed in the retainer and theunderlying aperture formed in the fuel tank wall;

FIG. 3a is an enlarged sectional view of the fuel tank apparatus of FIG.2 showing insertion of the valve assembly into the fuel tank through thepassageway formed in the retainer and the aperture formed in the fueltank wall and the retainer block deflecting the free-end portion of thering included in the retainer to a generally flat position adjacent tothe inner side of the body portion;

FIG. 3b is a view similar to FIG. 2 following insertion of the valveassembly through the passageway formed in the retainer and the apertureformed in the fuel tank wall showing the valve assembly being coupled tothe axially upper portion of the retainer and the axially lower portionof the retainer being welded to the exterior surface of the fuel tankwall;

FIG. 4 is a perspective view of an annular gasket shown in FIG. 3b;

FIG. 5 is a cross-sectional view of a mount ring coupled to the axiallyupper portion of the retainer and used to couple the valve assembly tothe retainer as shown in FIG. 3b, the mount ring including a fixed-endportion coupled to the body portion and a free-end portion extendinginto the passageway formed in the body portion;

FIG. 6 is a cross-sectional view taken along lines 6—6 of FIG. 3bshowing a weld flange including concentric spaced-apart contacts andshowing the free-end portion of the ring surrounding the valve assembly;

FIG. 7 is a cross-sectional view taken along lines 7—7 of FIG. 3bshowing the weld flange coupled to the exterior surface of the fuel tankwall and the valve assembly extending through the passageway formed inthe retainer;

FIG. 8 is a perspective view of the mount ring of FIG. 1;

FIG. 9 is a sectional detail view of the fuel tank and retainer of FIG.1 and a valve assembly in accordance with the present invention showinga ball-actuated closure valve included in the valve assembly and showinginsertion of the valve assembly into the fuel tank through thepassageway formed in the retainer and the aperture formed in the fueltank wall prior to deflection of the free-end portion of the ringincluded in the retainer; and

FIG. 10 is a view similar to FIG. 9 following coupling of the valveassembly to the axially upper portion of the retainer.

DETAILED DESCRIPTION OF THE DRAWINGS

As shown in FIG. 1, a fuel tank valve apparatus 10 includes a valveassembly 12 and a retainer 14 that couples valve assembly 12 in a fueltank 16. Retainer 14 is formed to be welded to fuel tank 16 to holdsecure valve assembly 12 in a fixed place in fuel tank 16. Specifically,retainer 14 prevents detachment of valve assembly 12 from fuel tank 16to permit valve assembly 12 to regulate the flow of liquid fuel and fuelvapor (not shown) from fuel tank 16 to a vapor recovery canister (notshown) or other destination outside fuel tank 16.

Referring now to FIG. 1, retainer 14 includes a body portion 18 formedto include a central passageway 20 and a weld flange 21 that extendsaway from passageway 20 for engagement with fuel tank 16. Retainer 14also includes a mount ring 22 that is distinct from body portion 18 andextends from body portion 18 into passageway 20. Further, body portion18 and ring 22 cooperate to hold valve assembly 12 therebetween so thatvalve assembly 12 is secured in a fixed position within fuel tank 16.While retainer 14 will be described with reference to fuel tank 16 andvalve assembly 12, it is within the scope of this disclosure to useretainer 14 to couple valve assemblies containing any number of valvestherein in a wide variety of fuel tanks.

Referring now to FIGS. 1 and 2, retainer 14 is formed to be coupled tofuel tank 16. Fuel tank 16 is constructed of a polymeric material thatlends itself to blow-molding, such as, for example polyethylene. Fueltank 16 includes a top wall 24 that has an exterior surface 26, to whichretainer 14 is coupled and an interior surface 28 located inside of fueltank 16. In addition, a vent-outlet aperture 30 is formed in top wall 24and extends between exterior and interior surfaces 26, 28.

Valve assembly 12 is retained in fuel tank 16 by retainer 14. Referringnow to FIGS. 2 and 3, valve assembly 12 includes a housing 32constructed from acetal and including a bottom end 33 having an inlet 35an annular mounting flange 58 near its top end 37 and an outlet portion39 coupled to top end 37 of housing 32 and formed to include a fuelvapor discharge tube 41. Referring to FIG. 2, outlet portion 39 ofhousing 32 has an upper portion 34 that remains outside of fuel tank 16.In addition, top and bottom ends 37, 33 define a lower portion 36 ofhousing that extends through passageway 20 into fuel tank 16 tocommunicate with fuel vapor and liquid fuel contained in fuel tank 16. Apartition 38 extends between upper portion 34 and lower portion 36.Partition 38 of housing 32 is formed to include an axiallydownwardly-facing, valve seat 40. Valve seat 40 defines an outlet 42.

Referring now to FIG. 3b, upper portion 34 of housing 32 is configuredto extend away from retainer 14 when the vale assembly 12 is in a fillymounted position in passageway 20 of retainer 14. Upper portion 34includes an interior wall 44 that defines a vapor-discharge chamber 46and a vapor-discharge opening 48. Lower portion 36 of housing 32 extendsthrough passageway 20 of retainer 14 and includes a generallycylindrical body portion 50. Body portion 50 includes an axially upperend 52, an opposite terminal end 54, and a central passage 56 extendingbetween upper and terminal ends 52, 54. In addition, lower portion 36includes a generally annular flange 58 appended to upper end 52 of bodyportion 50 and four retainer blocks 60 circumferentially spaced-apartfrom flange 58. As shown in FIGS. 1 and 2, retainer blocks 60 cooperatewith flange 58 to define a retention portion 62 therebetween.

Flange 58, as shown again in FIG. 3b, is sized to block movement of bodyportion 58 through passageway 20 of body portion 18 toward fuel tank 16.A gasket 64 is positioned to lie within retention portion 62 adjacent toflange 58 to establish a vapor and liquid seal between body portion 50and body portion 18 when flange 58 engages upper end 92 of body portion18. Gasket 64 is shown in FIG. 4 and includes an inner side 66 formed toengage body portion 50 and an outer side 68 formed to engage bodyportion 18. It will be appreciated that this sealed end connection couldbe accomplished in a number of different ways as long as fuel vapor orliquid fuel is unable to escape fuel tank 16 through the joint betweenflange 58 and body portion 18.

Retainer blocks 60, as shown in FIG. 2, are positioned to lie adjacentto notches 70 in body portion 50 and are formed to engage ring 22 toblock movement of body portion 50 through passageway 20 of body portion18 away from fuel tank 16 once valve assembly 12 is in the fully mountedposition. While only one retainer block 60 and notch 70 will bediscussed hereafter, the description applies to each retainer block andeach notch. Retainer block 60 projects in an axially upward directionaway from terminal end 54 of body portion 50 toward notch 70 formed inbody portion 50. Retainer block 60 includes an upwardly facing retainersurface 72 and an angled, radially outwardly facing cam surface 74 asshown in FIGS. 1 and 2. Retainer surface 72 is positioned so that itwill engage ring 22 when valve assembly 12 is moved toward the fullymounted position in passageway 20 as shown in FIG. 3b.

A valve 76 is installed in body portion 50 to control fluid flow throughoutlet 42. As shown in FIG. 2, valve 76 includes a first nipple 78, asecond nipple 80, and a float member 82 arranged in central passage 56of body portion 50. Float member 82 is movable in central passage 56 tocontrol the discharge of liquid fuel and pressurized fuel vapor fromfuel tank 16 through outlet 42 during, for example, sloshing of liquidfuel in fuel tank 16 as a result of vehicle movement of cornering,development of high pressure of fuel vapor in fuel tank 16, filling fueltank 16 with liquid fuel during refueling, and tilting or inversion ofvehicle containing tank as a result of vehicle rollover. Float member 82includes a top shell 84 formed to include second nipple 80 at its upperend 86. Reference is made to U.S. Patent Application entitled “Low-LeakTwo-Stage Reopening Device” to Dean C. Foltz which is filed herewith,for a description of a suitable valve for vent valve apparatus and whichis incorporated herein by reference.

As shown in FIG. 3b retainer 14 is coupled to lower portion 36 ofhousing 32 and lies between fuel tank 16 and upper portion 34 of housing32. Retainer 14 is constructed of a polymer that lends itself to weldingto fuel tank 16, such as, for example high density polyethylene. It iswithin the scope of this disclosure to construct retainer 14 from a widevariety of polymers suitable for welding to fuel tank 16.

Referring now to FIG. 3b, body portion 18 of retainer 14 is configuredto be coupled between flange 58 and retainer block 60 of body portion 50to block movement of valve assembly 12 in aperture 30 of fuel tank 16.As shown in FIG. 5, body portion 18 further includes an inner side 88configured to face body portion 50, an outer side 90, an axially upperportion 92 extending about the periphery of body portion 18, and anopposite lower portion 94. Inner side 88 of body portion 18 definespassageway 20 that extends between outer and lower portions 92, 94.

Weld flange 21 of body portion 18 is configured to be coupled toexterior surface 26 of fuel tank 16, as shown in FIGS. 5 and 7.Referring now to FIGS. 5 and 6, weld flange 21 extends from outer side90 of body portion 18 adjacent to lower portion 94. Weld flange 21includes circumferential weld feet or contacts 96 spaced-apart from oneanother. Contacts 96 are formed to engage exterior surface 26 of fueltank 16. Contacts 96 and fuel tank 16 are welded together using suitableknown techniques such as hot plate welding to establish a vapor andliquid seal therebetween. In addition, as shown in FIG. 2, weld flange21 has a pre-determined dimension 98 that is greater than a seconddimension 100 of aperture 30 to prevent retainer 14 from moving throughaperture 30.

Ring 22 of retainer 14 is constructed of a metal, such as for example,stainless steel. Continuing to refer to FIG. 2, ring 22 includes afixed-end portion 102 coupled to body portion 18 and an opposite rampedfree-end portion 104 extending into passageway 20 spaced-apart fromfixed-end portion 102. As best shown in FIGS. 5 and 8, fixed-end portion102 is generally L-shaped in cross-section and includes an inner surface106, an outer surface 108, and notches 1 10 extending between inner andouter surfaces 106, 108. Notches 110 disrupt inner and outer surfaces106, 108 to aid in gripping body portion 18. Additionally, free-endportion 104 includes tabs 112 positioned to lie in a spaced-apartrelationship relative to one another. Tabs 112 are separated by slots114. As shown in FIG. 5, free-end portion 104 normally flexes away frominner side 88 of body portion 18 to position free-end portion 104 in anormal elevated position. Given the flexibility of ring 22, free-endportion yieldably deflects to a generally flat position, adjacent toinner side 88 as shown by arrow 105 when pressed by retainer block 60,as will be discussed hereafter, as shown in FIG. 3a.

Valve assembly 12 and retainer 14 are manufactured separately andsubsequently assembled in an axial press-fit. In order to assemble fueltank valve apparatus 10, an assembly worker illustratively graspsretainer 14 and places contacts 96 of weld flange 21 upon fuel tank 16such that passageway 20 is aligned with aperture 30 in fuel tank 16, asshown in FIG. 5. Retainer 14 and fuel tank 16 are welded together usingsuitable known techniques such as hot plate welding. Thus, retainer 14is effectively integrated into fuel tank 16 by the welding process. Oncecoupled to fuel tank 16, retainer 14 is prevented from moving onexterior surface 26 of fuel tank 16.

Once retainer 14 has been coupled to fuel tank 16, valve assembly 12 iscoupled to retainer 14. Referring now to FIG. 2, the worker graspshousing 32 of valve assembly 12 and aligns body portion 50 withpassageway 20 of body portion 18. Once aligned, the worker simply slidesbody portion 50 through passageway 20 into aperture until side-face 74of retainer block 60 engages free-end portion 104 of ring 22. As shownin FIG. 3b, housing 32 is further pressed in an axially inwardlydirection as shown by arrow 116, yieldably biasing tabs 112 of free-endportion 104 in the radially inward direction as shown by arrow 105 untilflange 58 and free-end portion 104 engages upper portion 92 and retainersurface 72 of retainer block 66 respectively. Thus, inner side 92 ofbody portion 18 engages outer side 68 of gasket 64 to form a sealtherebetween As shown in FIG. 3b, once coupled to fuel tank 16, ring 22of retainer 14 fixes gasket 64 between flange 58 and retainer block 60,at all times being prevented from exiting passageway 20. Thus, bodyportion 50 is prevented from sliding through passageway 20 of retainer14 as well as aperture 30 in fuel tank 16.

Alternatively, a manufacturer may couple valve assembly 12 and retainer14 together prior to coupling retainer 14 to fuel tank 16. Valveassembly 12 and retainer 14 are coupled together as discussed above. Atthis time, body portion 50 is deposited into fuel tank 16 thoroughaperture 30 until contacts 96 engage exterior surface 26 of fuel tank16. Retainer 14 and fuel tank 16 are then welded together as discussedabove.

Referring now to FIGS. 9 and 10, retainer 14 is suitable for use withvalve assembly 212. Valve assembly 212 is described in U.S. Pat. No.4,655,238 to Szlaga, which is incorporated herein by reference. Valveassembly 212 includes a hollow valve housing 213 extending throughaperture 30 of fuel tank 16. Valve housing 213 has a lower rolloversafety portion 214 and an upper pressure-relief portion 216. Valveassembly 212 is constructed of acetal, although it is understood thatother materials can be used.

Lower roll-over safety portion 214 includes a top wall 215 and agenerally cylindrical side wall or body portion 217 that cooperate todefine a valve chamber 218 having an inlet 220 formed in side wall 217and an outlet 222 formed in top wall 215. Top wall 215 extends radiallyoutwardly from chamber 218 to define an upper flange 225. Inlet 220 isin fluid/vapor communication with a fuel tank or the like. Lower portion214 is also formed to include an axially downwardly-facing, generallyconical valve seat 223 in concentric registry with outlet 222. Inaddition, side wall 217 includes a lower flange or retainer block 227extending radially outwardly from chamber 218. Lower flange 227 includesa generally flat upper surface 229 and a tapered portion 231 thatextends between generally flat portion 229 and side wall 217. A gasket235 is positioned to lie between upper and lower flanges 225, 227 andincludes an inner end 237 engaging side wall 217 and an opposite outerend 239. Outer end 239 is generally convex in shape. It is within thescope of this disclosure to construct outer end 239 in a wide variety ofshapes and gasket 235 in a variety of sizes to accommodate various valveassemblies.

Upper pressure-relief portion 216 is formed to include an interior wall221 defining a vapor discharge chamber 224, and a passageway 226interconnecting vapor discharge chamber 224 and outlet 222 of valvechamber 218 in fluid/vapor communication. During vehicle operation, fuelvapors accumulated in the fuel tank are introduced into valve chamber218 under pressure. These fuel vapors are selectively transmitted viafluid-conducting passageway 226 to vapor discharge chamber 224 forsubsequent distribution to the canister (not shown) and to theatmosphere.

A roll-over assembly 230 is installed in lower portion 214 to controlfluid flow through fluid-conducting passageway 226. Roll-over assembly230 automatically closes valve chamber outlet 222 during vehiclerollover and change in vehicle motion to prevent the flow of liquid fueland/or fuel vapors through passageway 26 and into both of the canisterand the atmosphere. As shown best in FIGS. 9 and 10, roll-over assembly230 includes a valve member 232, a stainless steel ball 234, a ballretainer 236, and a valve member retainer 238.

Valve member 232 includes a downwardly opening ball-receiving cup 240and an integral upstanding valve stem 242. Valve stem 242 has a distal,spherical end 244 for engaging valve seat 223 to close chamber outlet222. An interior wall of cup 240 is configured to define a novel firstinclined ramp portion 246.

Ball retainer 236 includes a crisscross frame 252 for retaining ball 234in inverted cup 240. Crisscross frame 252 includes arms 256 each havinga distal end 258 and an outwardly turned L-shaped mounting tab 260extending upwardly therefrom for snapping into engagement with holes 262formed in the lowermost portion of inverted cup 240.

Valve member retainer 238 illustratively includes a base member 266 andwedge members 268 for retaining valve member and ball retainer assembly232, 236 in valve housing 213. The base member 266 includes mountflanges 270 for snapping into engagement with circumferentiallyspaced-apart channels 272 formed in the lowermost portion of valvehousing 213.

Valve assembly 212 and retainer 14 are manufactured separately andsubsequently assembled in an axial press-fit. In order to assemble fueltank valve apparatus 10, an assembly worker illustratively graspsretainer 14 and places contacts 96 of weld flange 21 upon fuel tank 16such that passageway 20 is aligned with aperture 30 in fuel tank 16. SeeFIG. 9. Retainer 14 and fuel tank 16 are welded together using suitableknown techniques such as hot plate welding. Thus, retainer 14 iseffectively integrated into fuel tank 16 by the welding process. Oncecoupled to fuel tank 16, retainer 14 is prevented from moving onexterior surface 26 of fuel tank 16.

Once retainer 14 has been welded to fuel tank 16, valve assembly 212 iscoupled to retainer 14. The worker aligns side wall 217 with passageway20 of body portion 18, as show in FIG. 9. Once aligned, the workersimply slides side wall 217 through passageway 20 as shown by arrow 299into aperture 30 until tapered portion 31 of lower flange 27 engagesfree-end portion 104 of ring 22. At this time, as shown in FIG. 10, sidewall 217 is further pressed in an axially inwardly direction yieldablybiasing tabs 112 of free-end portion 104 in the radially inwarddirection as shown by arrow 105 until upper flange 215 engages bodyportion 18 and tab 112 engages flat portion 229 of lower flange 227.

Alternatively, a manufacturer may couple valve assembly 212 and retainer14 together prior to coupling retainer 14 to fuel tank 16. Valveassembly 212 and retainer 14 are coupled together as discussed above. Atthis time, side wall 217 is deposited into fuel tank 16 thoroughaperture 30 until contacts 96 engage exterior surface 26 of fuel tank16. Retainer 14 and fuel tank 16 are then welded together as previouslydiscussed.

Although the invention has been described in detail with reference to apreferred embodiment, variations and modifications exist within thescope and spirit of the invention as described and defined in thefollowing claims.

What is claimed is:
 1. An apparatus for mounting a vent valve assemblyin an aperture of a fuel tank, the apparatus comprising a valve assemblyincluding a housing having a body, a flange coupled to the body, and aretainer block extending from the body and being spaced-apart from theflange and a valve positioned to lie in the housing, and a retaineradapted to be coupled to an exterior surface of the fuel tank, theretainer including a body portion defining a passageway being sized toreceive the body of the housing therein and a ring coupled to the bodyportion and extending into the passageway, the flange and retainer blockof the housing cooperating with the body portion and the ring of theretainer to couple the valve assembly and retainer together.
 2. Theapparatus of claim 1, wherein the ring includes a fixed-end portioncoupled to the body portion and a free-end portion positioned to lie inthe passageway.
 3. The apparatus of claim 2, wherein the fixed-endportion is formed to include notches.
 4. The apparatus of claim 2,wherein the free-end portion includes flexible tabs spaced apart fromone another.
 5. The apparatus of claim 1, wherein the retainer blockincludes a retainer surface positioned to face toward the flange and acam surface extending between the retainer surface and the body.
 6. Theapparatus of claim 5, wherein the ring engages the retainer surface whenthe flange engages the body portion to couple the body portion in thepassageway of the retainer.
 7. The apparatus of claim 1, wherein thebody portion is constructed of a polymer and the ring is constructed ofa metal.
 8. An apparatus for mounting a vent valve assembly in anaperture of a fuel tank, the apparatus comprising a valve assemblyincluding a housing having a body, a flange coupled to the body, and aretainer block extending from the body and being spaced-apart from theflange and a valve positioned to lie within the housing, and a retainerincluding a body portion formed to include an upper portion, a lowerportion, a passageway extending between the upper and lower portions andbeing sized to receive the body of the housing, and a weld flangeextending from the lower portion and adapted to be coupled to anexterior surface of the fuel tank and a ring coupled to the body portionand extending into the passageway, the flange and retainer block of thehousing cooperating with the upper portion and the ring of the retainerto couple the valve assembly and retainer together.
 9. The apparatus ofclaim 8, wherein the weld flange includes a contact extending away fromthe body portion and in spaced-apart relation to the body of thehousing.
 10. The apparatus of claim 9, wherein the weld flange includestwo concentrically aligned contacts.
 11. The apparatus of claim 8,wherein the ring is flexible and formed for movement in the passagewayupon movement of the retainer block in the passageway toward the lowerportion of the body portion.
 12. The apparatus of claim 11, wherein thering is constructed of a metal.
 13. The apparatus of claim 8, whereinthe retainer block includes a retainer surface positioned to face theflange and a tapered cam surface extending between the retainer surfaceand the body.
 14. The apparatus of claim 13, wherein the ring includes afixed-end portion coupled to the body portion and a free-end portionpositioned in the passageway.
 15. The apparatus of claim 14, wherein thecam surface is sized to press the ring toward the body portion uponmovement of the retainer block in the passageway toward the lowerportion of the body portion.
 16. A fuel tank assembly comprising a fueltank formed to include a wall having an exterior surface, an interiorsurface, and an aperture extending between the exterior and interiorsurfaces, a valve assembly including a housing having a body extendingthrough the aperture, a flange coupled to the body, and a retainer blockextending from the body and being spaced-apart from the flange, and aretainer including a body portion formed to include a weld flangecoupled to the exterior surface of the fuel tank and a passageway ingeneral alignment with the aperture of the fuel tank and sized toreceive the body of the housing and a ring coupled to the body portionand extending into the passageway, the flange and retainer block of thehousing cooperating with the body portion and the ring of the retainerto couple valve assembly and retainer together.
 17. The assembly ofclaim 16, wherein the fuel tank and the body portion of the retainer areconstructed of polymeric materials.
 18. The assembly of claim 17,wherein the ring is constructed of a metal.
 19. The assembly of claim16, wherein the weld flange includes contacts spaced apart from oneanother in engagement with the exterior surface of the fuel tank. 20.The assembly of claim 19, wherein the contacts extend about theperiphery of the aperture in the fuel tank.
 21. A tank valve apparatuscomprising a valve assembly and a retainer adapted to be coupled to anexterior surface of a tank, the retainer including a body portiondefining a passageway receiving the valve assembly therein and a mountcoupled to the body portion and extending into the passageway to retainthe valve assembly in the passageway.
 22. The apparatus of claim 21,wherein the mount includes a fixed-end portion coupled to the bodyportion and free-end portion having a plurality of tabs coupled to thefixed-end portion and arranged to extend into the passageway.
 23. Theapparatus of claim 22, wherein the tabs are positioned to lie incircumferentially spaced-apart relation to one another in thepassageway.
 24. The apparatus of claim 22, wherein each tab iscantilevered to the fixed-end portion and positioned to lie in thepassageway.
 25. The apparatus of claim 24, wherein each tab includes aradial section coupled to the fixed-end portion and a ramped sectioncoupled to the radial section and arranged to lie normally at an obtuseangle relative to the radial section.
 26. The apparatus of claim 22,wherein the tabs cooperate to define a deflectable conic section in thepassageway.
 27. The apparatus of claim 26, wherein the tabs arepositioned to lie in circumferentially spaced-apart relation to oneanother in the passageway.
 28. The apparatus of claim 22, wherein thebody portion includes an interior side wall defining the passageway andeach tab is hinged to the fixed-end portion to move through an anglefrom a normal position aligned at an acute angle relative to theinterior side wall to a deflected position aligned to lie alongside theinterior side wall during insertion of the valve assembly into thepassageway to assume a retained position therein.
 29. The apparatus ofclaim 28, wherein the valve assembly includes a housing containing avalve movable relative to the housing, a flange coupled to the housingand arranged to engage the body portion of the retainer upon movement ofthe valve assembly to assume the retained position in the passageway,and a retainer block coupled to the housing and arranged to lie inspaced-apart relation to the flange to trap the tabs therebetween uponmovement of the valve assembly to assume the retained position in thepassageway.
 30. The apparatus of claim 29, wherein the retainer blockincludes an angled, radially outwardly facing cam surface arranged tomove the tabs from the normal positions to the deflected positionsduring insertion of the valve assembly into the passageway and anupwardly facing retainer surface arranged to contact the tabs uponmovement of the valve assembly to assume the retained position in thepassageway.
 31. The apparatus of claim 22, wherein the fixed-end portionis encased in an interior region of the body portion.
 32. The apparatusof claim 31, wherein the fixed-end portion is ring-shaped.
 33. Theapparatus of claim 32, wherein the fixed-end portion includes an annularinner surface, an annular outer surface, and a plurality of notchesextending between the inner and outer surfaces.
 34. The apparatus ofclaim 21, wherein the body portion is made of a weldable polymericmaterial and the mount is made of a deflectable metal material.
 35. Theapparatus of claim 21, wherein the body portion includes a sleevedefining the passageway and a weld flange arranged to depend from thesleeve and adapted to be coupled to an exterior surface of a tank toalign the passageway with an opening in the tank.
 36. The apparatus ofclaim 35, wherein the weld flange includes two annular contacts arrangedto lie in concentric alignment with one another.
 37. The apparatus ofclaim 35, wherein the mount includes a fixed-end portion coupled to thebody portion and free-end portion having a plurality of tabs coupled tothe fixed-end portion and arranged to extend into the passageway. 38.The apparatus of claim 21, wherein the mount is ring-shaped.
 39. Theapparatus of claim 21, wherein the valve assembly includes a housingcontaining a valve movable relative to the housing, a flange coupled tothe housing and arranged to engage the body portion of the retainer uponmovement of the valve assembly to assume a retained position in thepassageway, and a retainer block coupled to the housing and arranged tolie in spaced-apart relation to the flange to trap the tabs therebetweenupon movement of the valve assembly to assume the retained position inthe passageway, the retainer block includes a retainer surfacepositioned to face the flange and a tapered cam surface extendingbetween the retainer surface and the body portion, the mount includes afixed-end portion coupled to the body portion and a deflectable free-endportion position in the passageway, and the tapered cam surface is sizedand arranged to press the deflectable free-end portion toward the bodyportion upon downward movement of the retainer block in the passagewayduring insertion of the valve assembly into the passageway.